A versatile clearing agent for multi-modal brain imaging.

Scientific reports (2015-05-08)
Irene Costantini, Jean-Pierre Ghobril, Antonino Paolo Di Giovanna, Anna Letizia Allegra Mascaro, Ludovico Silvestri, Marie Caroline Müllenbroich, Leonardo Onofri, Valerio Conti, Francesco Vanzi, Leonardo Sacconi, Renzo Guerrini, Henry Markram, Giulio Iannello, Francesco Saverio Pavone
ABSTRACT

Extensive mapping of neuronal connections in the central nervous system requires high-throughput µm-scale imaging of large volumes. In recent years, different approaches have been developed to overcome the limitations due to tissue light scattering. These methods are generally developed to improve the performance of a specific imaging modality, thus limiting comprehensive neuroanatomical exploration by multi-modal optical techniques. Here, we introduce a versatile brain clearing agent (2,2'-thiodiethanol; TDE) suitable for various applications and imaging techniques. TDE is cost-efficient, water-soluble and low-viscous and, more importantly, it preserves fluorescence, is compatible with immunostaining and does not cause deformations at sub-cellular level. We demonstrate the effectiveness of this method in different applications: in fixed samples by imaging a whole mouse hippocampus with serial two-photon tomography; in combination with CLARITY by reconstructing an entire mouse brain with light sheet microscopy and in translational research by imaging immunostained human dysplastic brain tissue.

MATERIALS
Product Number
Brand
Product Description

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